a) Field of the Invention
The invention is directed to a diode laser module which contains at least one bonded laser diode element and optical components on a common heat-dissipating carrier.
b) Description of the Related Art
The invention is further directed to a method for producing a diode laser module which contains at least one bonded laser diode element and optical components on a common heat-dissipating carrier, wherein the optical components are aligned and subsequently fixed in the operating state of the laser diode element.
Laser diode elements comprise individual laser diodes and laser diode bars. Individual laser diodes have only one individual laser diode emitter which is defined by an optically contiguous active zone. Laser diode bars are monolithic semiconductor laser arrangements of at least two laser diode emitters that are optically operational substantially independent from one another. The lateral extension of laser diode bars depends upon the width, spacing and quantity of emitters. Typical widths range from 1 mm to 15 mm.
As is well known, laser diode elements present difficulties in practical application because of their poor beam propagation characteristics.
Therefore, it is almost always necessary to optically transform the beam emitted by the laser diode element into a suitable form making use of the high output and favorable efficiency so that they are usable for the intended purpose.
The optics used for collimating, beam shaping and/or beam rearrangement were previously usually aligned by successive adjustment in the beam of the switched-on laser diode element and fixed successively in the aligned state.
Fixing by means of gluing has the disadvantage that outgassing can have a negative influence on the optical layers. Further, gluing technology can be automated only within limits because of long curing times. Further, shrinkage occurring during the hardening of the glue leads to unwanted changes in position of the optics so that the optical characteristics do not correspond to those of the optimal position.
While these disadvantages hinder reliable assembly with reproducible quality, the unfavorable aging behavior of the adhesives, which results in embrittlement, limits the life of the glue connections. This rules out, or at least severely limits, desirable long-term applications.